Immunologic and virologic characterization of two groups before and after challenge in study II. (a) Peak levels of SIV-specific IFN-γ ELISPOT responses to the MVTTioin+Adim or control vector regimen. (b) Comparison of Gag-specific CD8+ TEM polyfunctional responses in the peripheral blood with secretion of IFN-γ, TNF-α, and IL-2 between the two groups before viral challenge. (c) Comparison of neutralizing antibody responses against SIVmac1A11 between the two groups at peak and before viral challenge. (d and e) Temporal comparisons of plasma SIV RNA copies for up to 30 weeks after challenge or at the peak and set point. Error bars in panels b, c, and e represent SEM. *, P < 0.05; **, P < 0.01.